you may want to check out mt. hood summer ski camp, it's mostly racing and bumps but they have a small park thing. I went last year and there was like 10 kids in the park group, most of which were just starting to jump. But a couple of the staff are pretty good and their park is nice, its small, but the jumps are good. its one of the cheaper ones too.
'What is this rap trash? Soon you'll be dancin on the corner with the ho's and the shoota's!'